The invention generally relates to warning lights and, in particular, to emergency vehicle lighting, vehicle light bars and vehicle warning lights having one or more dichroic elements for creating multiple visible light signals of varying colors.
The use of absorptive filters in light bars and warning lights for emergency vehicles is well known. One major disadvantage with such absorptive filters is that they absorb light and thereby reduce the intensity of warning signals being provided to observers. In addition, the absorbed light creates heat in the absorptive filter which can be problematic.
There is a continuing need for warning lights which generate brighter signals, varying colored signals and multiple signals because such lights are usually more visible and usually are more effective in alerting observers. In addition, there is a continuing need to reduce power supply requirements. Although absorptive filters with multiple light sources may increase visibility, such a combination requires more power. Therefore, there is a need for warning lights which produce more visible signals without the concomitant increase in power needs.
In general, the invention meets the need for such warning lights in the form of a dichroic element in combination with a visible light source for use on a vehicle, particularly an emergency vehicle, to create a warning light signal provided to observers remote from the vehicle to alert the observers of the vehicle""s position.
In particular, the warning light of the invention provides many significant advantages over the prior art warning lights. For example, the invention provides the ability to efficiently generate multiple useable colors of light from a single visible light source. In addition, the invention provides more light signals in less occupied space for the same amount of amperage and for less absorbed heat than presently available conventional warning lights. Also, the warning signals of the invention tend to provide brighter photometrics for each color due to the ability to utilize various dichroic coatings providing complete color bands. The selectivity of dichroic coatings allows an entire allowable color band to be utilized. Further, the multicolor capability of the invention provides a very effective set of signals in a minimum amount of space. The use of a reduced number of light sources permits warning lights to have lower cost.
Other objects and features will be in part apparent and in part pointed out hereinafter.
In one form, the invention comprises an apparatus for a vehicle including a visible light source and a dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light generated by the light source and to reflect at least some of the visible light generated by the light source. The reflected light provides a warning light signal within a wavelength range when viewed by an observer remote from the vehicle.
In another form, the invention comprises an apparatus for a vehicle including a visible light source and a dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light generated by the light source and to reflect at least some of the visible light generated by the light source. The transmitted light provides a first warning light signal within a first wavelength range when viewed by an observer remote from the vehicle. The reflected light provides a second warning light signal within a second wavelength range different than the first wavelength range when viewed by an observer remote from the vehicle.
In another form, the invention comprises an apparatus for a vehicle including a visible light source and a dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light generated by the light source and to reflect at least some of the visible light generated by the light source. The transmitted light provides a first warning light signal having a first color when viewed by an observer remote from the vehicle. The reflected light provides a second warning light signal having a second color different than the first color when viewed by an observer remote from the vehicle.
In yet another form, the invention comprises a warning light mounted on a vehicle. The improvement comprises a visible light source and a dichroic element. The visible light source on the vehicle generates visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The dichroic element on the vehicle and adjacent to the visible light source transmits at least some of the visible light generated by the light source and reflects at least some of the visible light generated by the light source. The transmitted light provides a first warning light signal within a first wavelength range when viewed by an observer remote from the vehicle. The reflected light provides a second warning light signal within a second wavelength range different than the first wavelength range when viewed by an observer remote from the vehicle.
In another form, the invention comprises apparatus for a vehicle including a visible light source, a first dichroic element and a second dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The first dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to reflect at least some of the visible light generated by the light source. The light reflected by the first element provides a first warning light signal within a first wavelength range when viewed by an observer remote from the vehicle. The second dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to reflect at least some of the visible light generated by the light source. The light reflected by the second element provides a second warning light signal within a second wavelength range when viewed by an observer remote from the vehicle.
In another form, the invention comprises an apparatus for a vehicle including a visible light source, a first dichroic element and a second dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The first dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light generated by the light source and to reflect at least some of the visible light generated by the light source. The reflected light provides a first warning light signal within a first wavelength range when viewed by an observer remote from the vehicle. The second dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light transmitted by the first dichroic element to provide a second warning signal within a second wavelength range different than the first wavelength range when viewed by an observer remote from the vehicle. The second dichroic element reflects at least some of the visible light transmitted by the first dichroic element to provide a third warning signal within a third wavelength range different than the first and second wavelength ranges when viewed by an observer remote from the vehicle.
In yet another form, the invention comprises an apparatus for a vehicle including a visible light source, a first dichroic element and a second dichroic element. The visible light source is adapted to be mounted on the vehicle for generating visible light to be used to create warning signals which are viewed by observers remote from the vehicle. The first dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light generated by the light source and to reflect at least some of the visible light generated by the light source. The reflected light provides a first warning light signal within a first wavelength range when viewed by an observer remote from the vehicle. The second dichroic element is adapted to be mounted on the vehicle and adjacent to the visible light source to transmit at least some of the visible light reflected by the first dichroic element to provide a second warning signal within a second wavelength range different than the first wavelength range when viewed by an observer remote from the vehicle. The second dichroic element reflects at least some of the visible light reflected by the first dichroic element to provide a third warning signal within a third wavelength range different than the first and second wavelength ranges when viewed by an observer remote from the vehicle.
In another form, the invention comprises a method of making a warning light having a substrate with a dichroic coating thereon and having a light source. The warning light generates a visual warning signal including light having a particular wavelength range. The method comprises the steps of:
selecting a light source which emits light within the particular wavelength range;
selecting a dichroic coating which transmits or reflects light within the particular wavelength range; and
positioning the substrate to intersect light emitted by the light source whereby the intersected light is transmitted or reflected by the dichroic coating to form the warning signal.
In another form, the invention comprises a method of making a warning light having a substrate with a dichroic coating thereon and having a light source. The warning light generates a visual warning signal including light having a particular wavelength range. The method comprises the steps of:
selecting a dichroic coating which reflects light within the particular wavelength range; and
positioning the substrate to intersect light emitted by the light source whereby the intersected light is reflected by the dichroic coating to form the warning signal.